Enum ImageSource 

pub enum ImageSource {
    Named(String),
    Bytes(Arc<Vec<u8>>),
    Decoded(BitmapId),
}

Where a raster image’s pixels come from (docs/images.md).

One currency for both halves of the same question: Named is the staged asset every image(res::images::…) has always drawn, Bytes is an encoded PNG/JPEG the app already holds (a download, a file the user picked, a clipboard paste), and Decoded names an image the toolkit decoded once so several nodes (and the canvas) share it.

Variants

Named(String)

A staged asset name, resolved through the backend’s own pipeline (§18.2).

Bytes(Arc<Vec<u8>>)

Encoded bytes (PNG/JPEG/…) the app owns, decoded by the platform’s own decoder. Shared rather than copied: handing over a new buffer is a refcount bump.

Decoded(BitmapId)

An image already decoded through Toolkit::decode_image.

Trait Implementations

impl Clone for ImageSource

fn clone(&self) -> ImageSource

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ImageSource

Logs the buffer’s length, never its contents: a Debug that dumped a megabyte of pixels into a trace line would make the trace useless and slow.

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for ImageSource

fn default() -> ImageSource

Returns the “default value” for a type.

impl From<Arc<Vec<u8>>> for ImageSource

fn from(bytes: Arc<Vec<u8>>) -> ImageSource

Converts to this type from the input type.

impl From<BitmapId> for ImageSource

fn from(id: BitmapId) -> ImageSource

Converts to this type from the input type.

impl From<ImageName> for ImageSource

A staged asset name is a source, so image(res::images::cover) keeps compiling unchanged.

There is no From<&str> here, for the same reason resource::ImageName has none: image("typo") must stay a compile error rather than a blank view at runtime (resource.rs). A path or URL string is not a source either: read the bytes and hand those over.

fn from(name: ImageName) -> ImageSource

Converts to this type from the input type.

impl From<String> for ImageSource

An owned string is a name, not bytes: the same conversion resource::ImageName offers for a name computed at runtime, and the reason image(some_string) keeps compiling. A &str still converts nowhere, so image("typo") stays a compile error (resource.rs).

fn from(name: String) -> ImageSource

Converts to this type from the input type.

impl From<Vec<u8>> for ImageSource

fn from(bytes: Vec<u8>) -> ImageSource

Converts to this type from the input type.

impl From<VectorName> for ImageSource

fn from(name: VectorName) -> ImageSource

Converts to this type from the input type.

impl IntoImageSource<ImageValueMark> for ImageSource

fn into_image_source(self) -> Reactive<ImageSource>

impl PartialEq for ImageSource

Bytes compare by identity, not content.

This is the equality a binding gates on (§4.2), so it runs on every evaluation, and comparing two multi-megabyte buffers byte by byte would cost far more than the redundant decode it saves. Handing over a distinct buffer holding the same pixels therefore re-decodes, which is the same trade Arc::ptr_eq makes wherever else Day carries shared buffers.

fn eq(&self, other: &ImageSource) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.